A Phase II Trial of Isotretinoin and Alpha Interferon in Patients with Recurrent Squamous Cell Carcinoma of the Cervix: a Gynecologic Oncology Group Study

From January 1993 through January 1996, 37 patients with unresectable squamous carcinoma of the cervix were entered on study and scheduled to receive oral isotretinoin 1 mg/kg per day with subcutaneous alpha interferon 6,000,000 units/day. A course was defined as 4 continuous weeks of therapy. The mean number of four-course cycles delivered was 1.8. One patient was ineligible because of wrong cell type and two were never treated. Thus, 34 patients were evaluable for toxicity. Eight patients were inevaluable for response. Five did not receive a complete 4-week course and three did not have additional tumor measurements; thus 26 were evaluable for response. Prior radiotherapy had been given to 25 patients and prior chemotherapy to 23 patients. There was no grade 4 neutropenia. The incidence of Gynecologic Oncology Group (GOG) grade 3 granulocytopenia and thrombocytopenia was 8.8% and 5.8%, respectively. Six patients (17.6%) developed grade 3 or worse nausea and vomiting. Four (11.7%) patients developed grade 3 neurologic symptoms. There were no complete responses and one partial response. The overall response rate was 3.8% (95% confidence interval, 0.1-19.6%). In this pretreated population, isotretinoin and alpha interferon in the dose and schedule employed exhibit minimal activity.